Very specific SubRip question

[visitor13]

Every now and then when building a matrix I press a wrong key (or forget to deselect the Italic box). If I catch it right then can I go back and correct the mistake? So far I've been starting all over - which is a pain if you're almost done.

[niamh]

just carry on as normal, then go to edit/view character matrix at the top, you can modify everything from there, at any time.